On the Accretion Origin of a Vast Extended Stellar Disk around the Andromeda Galaxy
@article{Ibata2005OnTA, title={On the Accretion Origin of a Vast Extended Stellar Disk around the Andromeda Galaxy}, author={Rodrigo A. Ibata and Scott C. Chapman and Annette M. N. Ferguson and Geraint F. Lewis and Michael Irwin and Nial Tanvir}, journal={The Astrophysical Journal}, year={2005}, volume={634}, pages={287 - 313} }
We present the discovery of an inhomogenous, low surface brightness, extended disklike structure around the Andromeda galaxy (M31) based on a large kinematic survey of more than 2800 stars with the Keck DEIMOS multiobject spectrograph. The stellar structure spans radii from 15 kpc out to ~40 kpc, with detections out to R ~ 70 kpc. The constituent stars have velocities close to the expected velocity of circular orbits in the plane of the M31 disk and typically have a velocity dispersion of ~30…
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